Financial operations today are not restricted to face to face transactions with a bank teller or broker for every financial service desired by a customer. There are presently numerous ways to complete an electronic transaction remotely with a financial institution or service provider using external devices that can communicate with the bank over long distances via transmission lines. These external devices currently include automatic teller machines (ATMs), point-of-sale devices, home computers, touch-tone telephones, and intelligent phones capable of data and video display. The external devices can either connect to a financial institution or service provider directly via modem or be connected to a central switch that processes the transmissions and further communicates with the appropriate financial institution or service provider. The switch receives transmissions from the external devices, financial institutions and service providers constructed in a predetermined format called a protocol. The data carried in the transmissions are arranged in data constructs called data groups. Data groups must follow the prescribed protocol in order for the switch to properly interpret the information transmitted. Protocols typically require data items called "headers" and "trailers" to delineate when a group of messages start and end. There is always a corresponding trailer for each header transmitted.
U.S. Pat. No. 5,220,501 issued Jun. 15, 1993 to Lawlor et. al. discloses a method and system for conducting financial transactions using remote terminals. The remote terminals are connected to a central computer by a network switch. The central computer receives service requests from the remote terminals and then transmits messages over a conventional ATM network to a bank to complete a financial transaction. An example of a transaction performed by the system is cash withdrawal which debits a payer's account. Lawlor, however, does not disclose any particular protocol by which the service request data is transmitted. Lawlor discloses only a high level system and does not describe the details of the composition of the actual transmission.
There are a number of standard protocols that are used today and followed by programs run on external terminals that need to properly communicate with a central switch or other computer. One such protocol is the American National Standard for Electronic Data Interchange (ANSEDI) developed by the Accredited Standards Committee X12 and approved by the American National Standards Institute. ANSEDI can be used by a variety of industries including transportation, insurance, and retail purchasing to communicate information between two data processing systems. The ANSEDI protocol can also be used to transmit financial information.
The ANSEDI protocol requires data groups to be constructed with a particular arrangement of control messages. Each data group must start with a functional group header. Next, a transaction set header must be placed in the data group to designate a transaction set. Then a loop header designates the start of a bounded loop of data messages but is not part of the loop itself. Next, an inner loop header starts an inner, nested bounded loop of message instructions. Each header has a corresponding trailer placed in the data group to complete each nested loop. They appear in the following order and correspond to a previous header: inner loop trailer, loop trailer, transaction set trailer, and functional group header. More than one transaction set may be used within one functional group. Also, more than one bounded loop may be used within each transaction set.
Another standard protocol that is used today is the Electronic Data Interchange for Administration, Commerce and Transport (EDIFACT) agreed to by the United Nations Economic Commission for Europe. This protocol can be used between different remote sites located in different countries in order to provide proper communication that can be interpreted by both remote sites. EDIFACT has the limitation of only allowing messages of one service type to be present in a single data group to be transmitted. Thus additional data groups including headers and trailers must be transmitted to another computer in separate transmissions rather than in a single transmission. The extra required data is a disadvantage over a system that can transmit all the service types in one data group thereby reducing the number of headers and trailers in the transmission. Reduced data in the transmission can save transmission costs and processing time.